This invention relates to axial piston fluid pumping apparatus, and more particularly to an assembly of parallel cylinder sleeves for the axial pistons.
International Patent Application No. PCT/US96/12362 filed Jul. 24, 1996, for "Fluid Pumping Apparatus" and published as International Publication No. WO97/05382, discloses a compact axial piston pumping apparatus assembled from stacked components. The disclosure of the international application is hereby incorporated by reference as though fully set forth herein. One of the stacked components of the axial piston pumping apparatus is a cylinder sleeve member formed as a single extruded aluminum element. The cylinder sleeve member includes a large central opening and three cylinder bores symmetrically disposed about the central opening and parallel with each other. The central opening receives the shaft of a drive motor which mounts the pistons that operate in the cylinder bores.
The present invention is directed to an alternative construction for such a cylinder sleeve.